Every Barefoot Contessa fan knows "good olive oil" is a kitchen essential. But quality ingredients can cost: Ina Garten's personal favorite, Olio Santo, rings in at $60 for two bottles on Amazon.
Olive oil is a nearly holy "elixir" to some people, says Elizabeth Balkan, a director at sustainability organization Reloop North America. "It is so prized in my house, and when you're buying an expensive olive oil, there's been a lot of labor and love and time and process put into it."
In other words, it's almost sinful to throw it away, not to mention a waste of money.
Even if you aren't a consumer of pricey olive oil, you might have stocked up on one too many bottles in the midst of pandemic panic shopping and are now wondering if it's still OK to use a bottle that's been under your sink for almost a year.
Here's what to know about how long you should keep your olive oil and how to stretch its shelf life.
Heat, light, and oxygen all hasten olive oil deterioration, says Kate Merker, chief food director at the Good Housekeeping Institute.
"Once you open a bottle of oil, it's going to be the best if you use it within two to three months," she says. "If you're keeping it next to your stove, use it within two months."
This isn't a hard and fast rule, though. You can usually tell if olive oil has gone bad by its odor. "The sniff test is really where it's at," Merker says. "That's your biggest identifier if something has gone wrong."
In order to conduct an adequate sniff test, smell your olive oil upon opening it. Then, sniff it a couple times a week to see how the smell evolves. Keeping track of how different your olive oil smells from when you first opened it will make it easier to tell if its gone bad.
When it's ready to be thrown out, "some people say it smells like crayons or some sort of plastic," Merker says.
While most people store olive oil next to their stove, that's not actually the best place for it. "Home cooks should make an effort to keep olive oil in a dark, cool, not overly humid part of their kitchen or pantry to allow it to stay fresh and taste optimal for as long as possible," Balkan says.
So if you have an unopened bottle of olive oil in a cupboard, it's probably still good to use.
Olive oil will also last longer if you don't keep it in a transparent bottle. An aluminum bottle helps, Balkan says, because it's not translucent. On Amazon, a 101.4 ounce can of Filippo Berio Extra Virgin Olive Oil sold in a tin can retails for $23. If you don't want to keep a large, tin bottle of olive oil by your stove, you can pour a small amount in a different container and keep the tin under your sink, Balkan suggests.
Merker agrees that glass is not optimal if you want to keep your olive oil for longer: "A ceramic cruet is probably best. It blocks out light. It blocks out heat. You can get a stopper that will block out oxygen from getting in."
You can find a ceramic cruet at Bed Bath & Beyond for $10.
Because oxygen deteriorates olive oil, keeping olive oil in a jar that is too big for it could also shorten its shelf life, Merker adds. If you've used a decent amount of the olive oil in a bottle, move it to a smaller container where it won't have to sit with so much air.
If stored properly, olive oil can last for up to a year, experts say. This applies to both unopened bottles and opened, opaque bottles that aren't too large for the amount of oil you have.
Even if you can't cook with your olive oil anymore, there are other ways to get use out of it, Balkan says. "Scoring pans is one use," she says. "I also use olive oil for furniture and cutting boards as a conditioner and polisher."
If you're using it to polish furniture, mix it with an acid like vinegar or lemon juice, she suggests. The acid works as the cleaning agent and the oil works as the polisher.
If you must throw it out, remember not to pour it down the drain. "Households should never dispose of oil by flushing it down the toilet or pouring it down the drain," she says. "It's extremely harmful to your sewage system and septic system."
Instead, you should seal it tight in a container and throw it out with your trash.
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